package view;

import model.Table;
import org.jfree.chart.ChartPanel;

/**
 * a class of null mode
 * @author Rex
 *
 */
public class NullMode extends GeneralDisplayMode {

    /**
     * construct a class that does nothing
     */
    public NullMode() {
        super(null, null);
    }

    /**
     * construct a class that does nothing
     * @param myTable null
     * @param categoryNames null
     */
    public NullMode(Table myTable, String[] categoryNames) {
        super(myTable, categoryNames);
    }

    /**
     * sort ascending
     */
    public void sortAscending() {
        //do not sort 
    }

    /**
     * sort descending
     */
    public void sortDescending() {
      //do not sort 
    }

    /**
     * create an empty panel that occupies the graph panel
     * @return ChartPanel return the empty panel;
     */
    @Override
    public ChartPanel constructChartPanel () {
        ChartPanel panel = new ChartPanel(null);
        return panel;
    }
}
